Wind-electric installations (WPPs) convert the energy of movement of atmospheric masses, which is available to some extent at any point the globe, directly into electricity. It is on this that the positive economic and environmental effect of the use of wind turbines is based.

Benefits of wind energy

Modern technological solutions make it possible to produce wind generators with power from several kW to hundreds of MW. That is, wind turbines can provide electricity to both entire industrial areas and individual residential cottages. In addition to purely economic advantages, wind energy has another indisputable advantage - it has a significantly lower pressure on the ecology and biosphere of the Earth. Therefore, the authoritative website "Alternative Energy" (http://altenergiya.ru/) rightly confirms the deep thoughts of Vernadsky V.V., expressed back in the middle of the twentieth century:

… sales of small wind farms that are able to use wind power in almost any region (even where there is not enough wind power for industrial use) are constantly increasing. It is predicted that such alternative energy sources will be used more and more widely, both publicly and privately, until they finally replace traditional energy based on fossil fuels.

The economic advantages of household wind energy (installations with a capacity of 3 - 15 kW) include the following factors:

  • Inexhaustible source of energy;
  • Ecological purity of energy;
  • The speed of construction of a wind turbine;
  • Short payback period of capital investments;
  • No special sites for equipment installation are required.

The disadvantage of small wind turbines is practically one factor - the direct dependence of the generated power on the pressure of the air flow, which in most regions of the Earth is not stable. Therefore, for a stable and high-quality energy supply household appliances additional equipment such as batteries and semiconductor rectifiers is required.

Study of the energy potential of the territory

Looking into the future of the 21st century, the lack of alternatives for the development of wind energy is obvious. Therefore, in advanced countries, studies are being carried out on the potential of territories for the purpose of using them for the construction of large wind turbines.

Alternative energy stations usually occupy large areas. Accordingly, first of all, attention is drawn to such areas that, even in the distant future, cannot be involved in other economic activities:

  • Deserts;
  • mountain heights;
  • Shelf zones;
  • Coastal zones of the seas and oceans, and others.

In particular, the popular Internet resource windypower.blogspot.com/p/blog-page_8642.html provides the following information:

A preliminary study of the potential of the area is carried out. Anemometers are installed at a height of 30 to 100 meters, and within one to two years they collect information about the speed and direction of the wind. The information obtained can be combined into wind power availability maps. Such cards to potential investors to assess the rate of return on the project

Capacities of industrial wind farms

Industrial wind turbines come in a variety of capacities depending on the energy potential of a particular area. Modern technologies allow mass production of even non-standardized generator equipment with a payback period of 3-5 years.

Today, the largest land-based wind farm is located at the Tehachapi Pass in California. Its total capacity, commensurate with the capacity of large thermal power plants, is already 1550 MW.. In the future, it is planned to increase the installed capacity of ALTA WPP to 3,000 MW. It uses wind turbines of 1.5 and 3.0 MW.

Powers that own large offshore zones are actively developing offshore wind energy. Denmark and the UK are leading in this area. Such wind turbines are installed 10-50 km from the coast in the sea with shallow depths and are highly efficient, because constant sea winds blow there. The largest wind farm operating in the offshore areas of the world is the British station London Array with an operating capacity of 630 MW.

Such exotic types of wind farms as floating and soaring are also developing. So far, these are installations with one or a small group of generators with a capacity of 40-100 kW each. But over time, it is planned to increase the capacity of units at floating power plants to 6.3 MW. In particular, Danish and Italian firms have already come close to such capacities.

WPP for providing electricity to cottages and small businesses and their prices.

In order to fully cover the needs of a country house, not a large farm, restaurant or market, it is enough to have an installation with a capacity of 20 kW or even less. For a residential building, for example, the rated power of the generator is selected at the rate of 1 kW per 12 m2 of area, if the winter temperature does not fall below 18C with an average daily wind speed of 6.3 m/s or more.

The cost of a power plant for household needs and small businesses depends on the rated power of the electric generator and is about 50 thousand rubles per 1 kW for wind farms up to 3 kW, 40 thousand rubles / kW for wind farms up to 10 kW and about 30 thousand rubles / kW - for wind farms over 10 kW.

The payback of an autonomous power plant is within 5 - 7 years, so 1 kW of the installed rated power of the generator can generate so much energy per year that is equivalent to burning 2 tons of high-quality coal. In particular, the wind turbine "ESO-0020" with a rated electric power of 20 kW, presented on the website "Training materials of VSUES (http://abc.vvsu.ru/) has the following parameters:

  • The cost of electricity - 0.02 USD / kWh;
  • Annual output of el. energy - more than 70,000 kWh;
  • Payback period - up to 7 years;
  • Service life - 20 years.

Video

Wind power plant (WPP) is an alternative environmentally friendly source of energy. A WPP is a number of distributed or concentrated wind power plants (wind turbines or wind turbines) connected to a common network (cascades). The largest wind farms can consist of hundreds or more wind turbines operating both on their own and on one common power unit. For wind farms, regions with an average wind speed of more than 4.5 m/s are the most efficient.

Russia has large wind energy resources, the total wind potential of the country is estimated at approximately 14,000 TWh/year. The largest wind farm in Russia is the Zelenograd wind farm (5.1 MW), we also note the Anadyr wind farm, the Zapolyarnaya wind farm and the Tyupkilda wind farm. The total capacity of operating wind farms in Russia is more than 16.5 MW. In addition to electricity, wind energy is used to obtain thermal and mechanical energy.

"Zelenograd wind turbine is located near the village of Kulikovo, Zelenograd district, Kaliningrad region.

The wind turbine converts the kinetic energy of air flows into mechanical energy, which is used to rotate the rotor of the electric current generator. Industrial wind turbines are used in the construction of wind farms. Their power can reach 7.5 MW, it depends on the design of the windmill, the strength of the air flow, air density and the area of ​​the blown surface. An industrial wind turbine usually consists of a foundation, a power control cabinet, a tower, a ladder, a turning mechanism, a nacelle, an electric generator, a wind tracking mechanism, a braking system, a transmission, blades, a fairing, communications, and a lightning protection system. Wind turbines come with a vertical axis of rotation (rotary blades, etc.) and horizontal-axial - circular rotation, the most common because of their simplicity and high efficiency.

The device of the wind generator includes a wind turbine (spun by blades or a rotor) and an electric generator. The electricity received from the generator is usually supplied to the battery management device, after which it is accumulated in the batteries, and with the help of an inverter connected to the mains, it is converted into alternating current of the required strength, frequency and voltage (for example: 50 Hz / 220 V). The wind turbine at the output of the electric regulator has 24, 48 or 96 volts direct current. The battery packs store energy for use when there is no wind. The circuit diagram of the interaction of wind turbines with devices can be modified and improved in any way.

Types of wind power plants.

Ground - the most common type. Wind generators are located here on hills (mountains, hills). The largest wind farm is the California Alta in the United States with a capacity of 1.5 GW. Wind generators at an altitude of more than 500 m above sea level are a mountainous variety of ground stations.

Shelf is built in the sea, 10-60 km from the coast. It gives an advantage in the absence of dedicated land territories and high efficiency due to the constancy of sea winds. Compared to ground, it is more expensive.

The UK's largest London Array produces 630 MW of electricity.

Coastal is built in the coastal zones of the seas and oceans, which is due to daily sea breezes.

Floating is a relatively new species. It is installed on a floating platform at some distance from the coast.

Soaring, where wind turbines are placed high above the ground in order to use stronger and more persistent air currents.

Wind turbine advantages:

  1. Cheap installation and maintenance
  2. No need for large staff
  3. Environmental friendliness (even when destroyed), no emissions into the atmosphere, violation of the ecosystem and landscape
  4. Renewability of the energy source
  5. No need for a dedicated dedicated area around the station
  6. High level of net profit to owners due to high ratio modern value electricity to the minimum cost of obtaining this energy

Wind turbine disadvantages:

  1. High entry barrier to business. Wind farm construction, accurate location calculations based on years of readings
  2. impossibility accurate forecast the amount of energy produced due to the natural nature of the wind
  3. low power
  4. High noise levels that can adversely affect environment(however, modern technologies make it possible to achieve an approximation of the noise level to the level natural environment already 30 meters from the turbine)
  5. Possibility of harm to birds and distortion of TV and radio signals

Wind turbine projects of the future:

Windstalks instead of blades. Installation in the Masdara car-free green city project near Abu Dhabi. 1203 energy-efficient stems 55 m high at a distance of 10-20 m from each other will "grow" from the ground, sway from the wind and thus generate energy by compressing the ceramic disks of the electrode layers.

The super-massive Aerogenerator X wind turbine differs from classic wind turbines with its impressive size and 3 times more energy than a conventional wind turbine (10 MW). The blade span is 275 m. The design is used in width, not up. The windmill rotates over the sea surface like a carousel.

Norwegian city of turbines on the coast of Stavanger. Since the European Union has set the goal of providing energy for at least 20% of natural forces, then it is possible that Norway will become the main producer of energy through wind and water. Many connected wind turbines will be a real city with two million jobs. This energy should be enough for Norway and part of Europe. By 2020, the developers expect to provide 12% of the energy of the world's energy. The clean turbines will save more than 10,700 million tons of carbon dioxide emissions.

wind energy

The energy of moving air masses is enormous. The reserves of wind energy are more than a hundred times greater than the reserves of hydropower of all the rivers of the planet. Winds blow constantly and everywhere on earth - from a light breeze that brings the desired coolness in the summer heat to mighty hurricanes that bring incalculable damage and destruction. The air ocean at the bottom of which we live is always restless. The winds blowing in the vastness of our country could easily satisfy all its needs for electricity! Why is such a plentiful, affordable and environmentally friendly source of energy so poorly used? Today, wind-powered engines cover only one thousandth of the world's energy needs.

Even in ancient Egypt, three and a half thousand years before our era, wind engines were used to lift water and grind grain. For more than fifty centuries, windmills have hardly changed their appearance. For example, in England there is a mill built in the middle of the 17th century. Despite her advanced age, she still works hard to this day. In Russia, before the revolution, there were approximately 250 thousand windmills, the total capacity of which was about 1.5 million kW. They grind up to 3 billion poods of grain per year.

The technology of the 20th century has opened up completely new opportunities for wind energy, the task of which has become different - to generate electricity. At the beginning of the century, N. E. Zhukovsky developed the theory of a wind turbine, on the basis of which high-performance installations capable of receiving energy from the weakest breeze could be created. Many projects of wind turbines have appeared, incomparably more advanced than the old windmills. Achievements of many branches of knowledge are used in new projects.

Windmills have proven to be excellent sources of free energy. It is not surprising that over time they began to be used not only for grinding grain. Windmills rotated circular saws at large sawmills, lifted loads to great heights, and were used to lift water. Along with water mills, they remained, in fact, the most powerful machines of the past. In the same Holland, for example, where there were the most windmills, they successfully worked until the middle of our century. Some of them are still active today.

Interestingly, mills in the Middle Ages aroused superstitious fear among some - even the simplest mechanical devices were so unusual. Millers were credited with communicating with evil spirits.

Nowadays, the design of a wind wheel, the heart of any wind power plant, is being carried out by aircraft builders who are able to choose the most appropriate blade profile and study it in a wind tunnel. Through the efforts of scientists and engineers, a wide variety of designs of modern wind turbines have been created.

Types of wind turbines

Developed a large number of wind generators. Depending on the orientation of the axis of rotation with respect to the direction of flow, wind turbines can be classified:

With a horizontal axis of rotation parallel to the direction of the wind flow;
with a horizontal axis of rotation perpendicular to the direction of the wind (similar to a water wheel);
with a vertical axis of rotation perpendicular to the direction of the wind flow.

Here is the wind power website. NPG "Signmet" is a domestic DEVELOPER and MANUFACTURER of wind power plants (wind generators), one of the world leaders in the field of autonomous wind power - the owner of the Grand Prix and three gold medals of the World Brussels Exhibition of Innovations "Eureka-2005". NPG "SAINMET" presents autonomous wind power plants: a wind generator with a capacity of 5 and a wind generator with a capacity of 40 kW, as well as wind solar and wind diesel installations based on them.

Wind-diesel power plants can be combined into local networks, as well as interfaced with solar panels. Wind-diesel units, depending on the wind potential of the area, can save 50-70% of the fuel consumed by diesel generators of comparable power.

The main design solutions of wind turbines are protected by patents for inventions.

Wind energy

Man has been using wind energy since time immemorial. But his sailboats, which plied the vastness of the oceans for thousands of years, and windmills used only a tiny fraction of those 2.7 trillion. kW of energy possessed by the winds blowing on Earth. It is believed that it is technically possible to develop 40 billion kW, but even this is more than 10 times the planet's hydropower potential.

Why is such a plentiful, affordable and environmentally friendly source of energy so underused? Today, wind-powered engines cover only one thousandth of the world's energy needs.

The wind energy potential of the Earth in 1989 was estimated at 300 billion kWh per year. But only 1.5% of this amount is suitable for technical development. The main obstacle for him is the absent-mindedness and inconstancy of wind energy. The volatility of the wind requires the construction of energy accumulators, which significantly increases the cost of electricity. Due to absent-mindedness, the construction of solar and wind power plants of equal capacity requires five times more area for the latter (however, these lands can be simultaneously used for agricultural needs).

But there are also regions on Earth where the winds blow with sufficient constancy and force. (Wind blowing at a speed of 5-8 m/s is called moderate, 14-20 m/s is strong, 20-25 m/s is stormy, and over 30 m/s is called hurricane). Examples of such areas are the coasts of the North, Baltic, and Arctic seas.

The latest research is focused mainly on obtaining electrical energy from wind energy. The desire to master the production of wind power machines led to the birth of many such units. Some of them reach tens of meters in height, and it is believed that over time they could form a real electrical network. Small wind turbines are designed to supply electricity to individual houses.

Wind power stations are being built mainly with direct current. The wind wheel drives a dynamo - an electric current generator, which simultaneously charges parallel-connected batteries.

Today, wind turbines reliably supply electricity to oil workers; they successfully work in hard-to-reach areas, on distant islands, in the Arctic, on thousands of agricultural farms where there are no large settlements and public power plants.

The main direction of using wind energy is to obtain electricity for autonomous consumers, as well as mechanical energy for raising water in arid regions, pastures, draining swamps, etc. In areas with suitable wind conditions, wind turbines complete with batteries can be used to power automatic weather stations , signaling devices, radio communication equipment, cathodic protection against corrosion of main pipelines, etc.

According to experts, wind energy can be effectively used where short-term interruptions in energy supply are acceptable without significant economic damage. The use of wind turbines with energy storage allows them to be used to supply energy to almost any consumer.

Powerful wind turbines are usually located in areas with constantly blowing winds (on sea coasts, in shallow coastal areas, etc.). Such turbines are already used in Russia, the USA, Canada, France and other countries.

The widespread use of wind power units under normal conditions is still hindered by their high cost. It hardly needs to be said that there is no need to pay for the wind, but the machines needed to harness it to work are too expensive.

When using wind, a serious problem arises: an excess of energy in windy weather and a lack of it during periods of calm. How to accumulate and store wind energy for the future? The simplest way is for a wind wheel to drive a pump that collects water in a reservoir above, and then the water drains from it to drive a water turbine and a DC or AC generator. There are other ways and projects: from conventional, albeit low-power batteries to spinning giant flywheels or forcing compressed air into underground caves, and up to the production of hydrogen as fuel. The latter method seems to be especially promising. Electricity from a wind turbine decomposes water into oxygen and hydrogen. Hydrogen can be stored in liquefied form and burned in the furnaces of thermal power plants as needed.

Literature

    Science and Life, No. 1, 1991. Moscow: Pravda.

    Technique of Youth, No. 5, 1990

    Felix R. Paturi Architects of the XXI century M.: PROGRESS, 1979.

    Science and Life, No10, 1986. Moscow: Pravda.

    Bagotsky V.S., Skundin A.M.

    Chemical power sources, Moscow: Energoizdat, 1981. 360 p.

    Korovin N.V. New chemical current sources, Moscow: Energiya, 1978. 194 p.

    Dr. Dietrich Berndt Design Level and Technical Limits of Application of Sealed Batteries A/O VARTA Betteri Research and Development Center

    Lavrus V.S. Batteries and accumulators K.: Science and technology, 1995. 48 p.

    Science and Life, No. 5 ... 7, 1981 M .: True.

    Murygin I.V. Electrode processes in solid electrolytes. Moscow: Nauka, 1991. 351 p.

    The Power Protection Handbook American Power Conversion

    Shults Yu. Electrical measuring equipment 1000 concepts for practitioners. Moscow: Energoizdat, 1989. 288 p.

    Science and Life, No. 11, 1991. Moscow: Pravda.

    Yu. S. Kryuchkov, I. E. Perestyuk Wings of the Ocean L.: Shipbuilding, 1983. 256 p.

    V. Bryukhan. Wind energy potential of the free atmosphere over the USSR Metrology and hydrology. No. 6, 1989

    New scientist #1536, 1986

    Daily Telegraph, 09/25/1986

The frame of one-story buildings consists of transverse frames, hinged on top with truss structures. The transverse rigidity of the building is provided by columns rigidly fixed in the foundation and the roof disk.

In buildings with a roof arranged on a solid flooring of large-sized reinforced concrete slabs, the operating conditions of individual frames are facilitated due to the partial transfer of loads from the “rigid” roof to adjacent frames.

Buildings with a roof made of slabs laid along girders are in less favorable conditions, because the independence of the deformation of individual frames when exposed to local loads can lead in some cases to a deterioration in the operational properties of the building.

Therefore, when designing buildings with bridge cranes of significant carrying capacity, as well as craneless cranes with a large height, longitudinal connections should be provided along the upper chords of truss structures, to some extent combining the work of frames in the transverse direction.

Ensuring the rigidity of the building in the longitudinal direction only due to columns is economically justified only for craneless buildings: with spans L≤ 24 m and heights H ≤ 8.4 m, as well as for buildings with L= 30 m and H ≤7.2 m. For buildings of great height and buildings with overhead cranes, it is necessary to provide vertical stiffeners in the longitudinal direction.

Such connections are arranged between the columns and, if necessary, in the covering of the building.

The transfer of wind loads from the end walls to the columns and vertical connections through the roof structures is only advisable for buildings of certain spans and heights. In large-span buildings of more or less significant height, such use of the roof makes it difficult to attach the roof structures to the columns, complicates the structures that ensure the stability of the coatings, and in some cases cannot be carried out at all without violating the integrity of the roof, the strength of its fastenings to the roof structures.

The end walls of such buildings should be designed using horizontal wind farms and transferring the vast majority of the wind load to them.

Roofs made of relatively small products laid along the girders can perceive wind loads from the end walls and transfer them to the columns only if they are decoupled by a system of transverse horizontal ties along the upper chords of the truss structures.

The conditions for the use of such, as well as other secondary structures (vertical connections between trusses, braces, stretch marks) depend on the parameters of the building.

All one-story industrial buildings are divided into structurally homogeneous groups depending on the type of transport equipment and overall characteristics (span and height), which are shown in table 1 below.

Group I includes buildings with spans up to 24 m, having a height of up to 8 m, as well as buildings with spans of 30 m and a height of up to 7 m.

Group II includes buildings with transverse expansion joints at: L= 18 m and H = 9 - 15 m; L= 24 m and H = 9 - 12 m; L≥ 30 m and H = 9 - 10 m;

Group III includes buildings with transverse expansion joints, but higher than the buildings of group II, as well as buildings without transverse expansion joints with spans L= 18 m, 24 m, 30 m, over 12 m high.

All buildings of the specified nomenclature, with the exception of buildings of group A - b - I, require the use of connections.

Table 1

Group of buildings by height with roofless roofs with purlin roof
with overhead cranes without overhead cranes with overhead cranes without overhead cranes
Low A - a - I A - b - I B – a – I B – b – I
Medium A - a - II A - b - II B – a – II B – b – II
High A - a - III A - b - III B – a – III B –b – III

Vertical stiffeners between columns are installed in the middle of the temperature block of each longitudinal row. In buildings with overhead cranes, vertical connections along the columns are arranged only to a height to the bottom of the crane beams (Fig. 1), and in buildings without overhead cranes - to the full height of the columns. Between the steel columns of crane buildings, connections are also installed in the over-crane parts of the columns, both in the middle of the temperature block and in its extreme steps (Fig. 2 a, b). When the height of the crane part of the steel column exceeds 8.5 m, the connections are doubled (Fig. 2 c).

According to the scheme, steel connections between columns are divided into cross and portal. The cross ones are characterized by 6-meter steps of the columns, the portal ones - by 12 meters.

2. Vertical connections on steel columns:

a - cross connections; b - portal connections; c - cross double bonds

The main walls, located between the columns and firmly connected to them, can be used to provide longitudinal rigidity of the building instead of vertical ties only if it is guaranteed that these walls will not be subject to dismantling during the operation or reconstruction of the building.

In all buildings with purlin roofing, it is necessary to provide for horizontal transverse stiffeners, which are installed along the upper chords of truss structures in the extreme panels of each temperature block, regardless of the presence or absence of wind farms.

In tall buildings, horizontal wind farms are required at the ends of buildings. In buildings with overhead cranes, wind farms are installed at the level of the top of the crane beams (Fig. 3).

Rice. 3. Layout of the wind farm at the level of crane beams

To transfer the pressure of wind farms along the line of crane beams, the gaps between the ends of the beams are filled with concrete, and the fastening of the crane beams to the columns of the tie panel is calculated on the perception of all horizontal forces (including forces from longitudinal braking of cranes) acting along the line of crane beams.

In buildings without overhead cranes, wind farms must be located at the level of the top of the vertical ties.

In all cases of using wind farms in buildings without truss structures, spacers must be placed between the columns at the level of wind farms to transfer wind pressure from farms to vertical ties.

In buildings with truss structures, their fastening to columns is calculated for horizontal loads from wind farms. The gaps between the ends of the sub-rafter structures are recommended to be filled with concrete.

All longitudinal loads taken by individual elements of the building must ultimately be transferred to vertical braces in the longitudinal rows of columns or distributed between the columns. The need for secondary devices to ensure the strength of the nodes and the stability of the coating elements involved in such a transfer is largely determined by the type of roof.

In buildings of types A - a - I, II, III and A - b - I with rigid roofless roofs, wind loads are distributed by the coating between all columns in longitudinal rows. The fastening of each of the truss structures to the columns in these cases should be calculated for the part of the total wind load it perceives.

If it is impossible to provide the necessary strength for attaching truss structures to columns (for example, in coatings with truss structures with great height on supports) establish vertical connections between the support posts of the truss structures in the extreme panels of the temperature block. At the same time, spacers are also installed between all columns of a row along their heads to distribute, perceived by a vertical connection, wind pressure between all columns of a row.

In buildings of type A - b - II, in which vertical connections between columns are arranged for the entire height of the columns, wind forces are transmitted by the coating to the columns only at the attachment points of the truss structures to the columns of the connection panel. In this case, it is necessary to arrange additional links in the coverage. So, with a small height of the truss structures, spacers are installed on the support between the columns of each longitudinal row, transferring wind loads to vertical connections. The fastening of each of the truss structures to the columns will then work only on the part of the total wind load that falls on it. And with a significant height of the truss structures on the support (steel and reinforced concrete trusses with parallel chords, reinforced concrete beamless trusses, etc.), vertical connections (C1) should be installed between the supporting posts of the trusses at the extreme steps of the temperature block, connected by a continuous chain of spacers. Steel roof trusses are additionally untied along the lower chords with braces (C2) and attached to the rest of the trusses with braces along the lower chord (C3) and struts along the upper chord (C4) (Fig. 4).

Rice. 4. Scheme of bonds in the coating on steel girders

In buildings with overhead cranes of heavy or especially heavy duty, spacers (C5) and braces (C6) are installed along the longitudinal edges of each temperature block at the level of the lower belt of truss trusses (Fig. 4).

In buildings with lanterns, spacers are installed within the lantern in the middle of the span, connecting the nodes of the upper chords of the truss structures, as well as vertical and horizontal connections in the extreme steps of the temperature block.

Connections are designed from rolled, bent, bent-welded profiles or electric-welded pipes.

They are fastened with bolts of normal accuracy or high strength, as well as by welding.

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Using wind energy to generate electricity is a logical desire for a home owner, especially if the home is located on a hill and is constantly exposed to wind loads. A windmill for a private house at this stage of technology development will not become cheaper than electricity purchased in the general power grid, but it can give the desired independence.

preliminary calculations

The first stage is to analyze the development and openness of the site where you plan to install a windmill for your private house. Keep in mind that the moving part of this windmill must be above the tallest building and tree.

Step two is to analyze the archive of the weather report in your area. Such an archive is most widely represented on the site gismeteo.ru (opens in a new window). To obtain data, use the service for schoolchildren:

At correct location windmill in your home, the direction of the wind will not matter, only its speed will matter.

Stage three - counting windy days. To one degree or another, every day is windy, but not every wind can turn a windmill. It all depends on the chosen model of wind farm. The most expensive wind turbines for private homes, such as the American turbine Windtronics can start generating current at 1 m/s, but most factory generators start at 3-4 m/s. Therefore, when calculating the weather archive, feel free to subtract those days in which the wind speed is less than the declared minimum on the device.

American windmill Windtronics for $5800

Stage four - calculation of energy efficiency. The faster the windmill rotates, the more electricity will be in your private home. When calculating the efficiency of a wind farm, calculate the average wind speed based on the data obtained from the diary and multiply by 2,4 - get the number of hours the windmill operates per year. 2,4 – this is 10% of 24 hours – in weather conditions Russia - the average amount of time that the wind blows.

Consider the calculation of efficiency on the example of a wind farm energy wind 1 kW, which will operate in the village of Yastrebovo (Moscow Region):

  • We count all the days in which the wind speed exceeded 3 m / s (lower threshold for this windmill) = 219;
  • We calculate the arithmetic mean of these speeds = 1352/219=6.17 ( average speed wind);
  • At this speed, the wind generator produces 0.3 kW / h, multiply this figure by 2.4 (time real work windmill per day) and get 0.72 kWh per day;
  • We multiply by the number of windy days in a year 219 * 0.72 = 157.68 kW you will receive in one year of operation of such a wind generator

A lot or a little - you decide. The cost of such a windmill is 862$ . The current electricity tariff is 0,06$ . Therefore, such a windmill will save you 157.68 * per year 0,06 $ = 9,4$ , and for 10 years (service life of the device) - almost 100$ .

Not everything is measured in money

A windmill for a home is justified in a limited number of cases:

  • In the absence of the possibility of connecting to a common power grid;
  • When making a windmill with your own hands from improvised materials;
  • If you are an active participant in the movement for the preservation of the environment on the planet.

There is no other reason to install wind farms to power your own home. Even if your home is located in a geographic environment where there is a constant flow of wind, this will not make a home windmill economically viable.

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Air masses have inexhaustible reserves of energy that mankind used in ancient times. Basically, the force of the wind ensured the movement of ships under sail and the operation of windmills. After the invention of steam engines this species energy has lost its relevance.

Only in modern conditions, wind energy has again become in demand as a driving force applied to electric generators. They are not yet widely used on an industrial scale, but are becoming increasingly popular in the private sector. Sometimes it is simply impossible to connect to the power line. In such situations, many owners design and manufacture a wind generator for a private house with their own hands from improvised materials. In the future, they are used as the main or auxiliary sources of electricity.

The theory of an ideal windmill

This theory was developed in different time scientists and specialists in the field of mechanics. It was first developed by V.P. Vetchinkin in 1914, and the theory of an ideal propeller was used as a basis. In these studies, the utilization factor of wind energy by an ideal windmill was first derived.

Work in this area was continued by N.E. Zhukovsky, who deduced the maximum value of this coefficient, equal to 0.593. In the later works of another professor - Sabinin G.Kh. the corrected value of the coefficient was 0.687.

According to the developed theories, an ideal wind wheel should have the following parameters:

  • The axis of rotation of the wheel must be parallel to the speed of the wind flow.
  • The number of blades is infinitely large, with a very small width.
  • Zero profile resistance of the wings in the presence of constant circulation along the blades.
  • The entire swept surface of the windmill has a constant lost airflow velocity on the wheel.
  • The tendency of the angular velocity to infinity.

Wind turbine selection

When choosing a wind generator model for a private house, one should take into account the necessary power that ensures the operation of instruments and equipment, taking into account the schedule and frequency of switching on. It is determined by monthly metering of consumed electricity. Additionally, the power value can be determined in accordance with the technical characteristics of consumers.

It should also be taken into account that the power of all electrical appliances is not carried out directly from the wind generator, but from the inverter and a set of batteries. Thus, a generator with a power of 1 kW is able to ensure the normal functioning of the batteries that feed the four-kilowatt inverter. As a result, household appliances with a similar capacity are provided with electricity in full. Of great importance right choice batteries. Special attention should pay attention to parameters such as charging current.

When choosing a wind turbine design, the following factors are taken into account:

  • The direction of rotation of the wind wheel is vertical or horizontal.
  • The shape of the blades for the fan can be in the form of a sail, with a straight or curved surface. In some cases, combined options are used.
  • Material for blades and technology of their manufacture.
  • Placement of fan blades with different slopes relative to the flow of passing air.
  • The number of blades included in the fan.
  • The required power transferred from the wind turbine to the generator.

In addition, it is necessary to take into account the average annual wind speed for a particular area, specified in the meteorological service. It is not necessary to specify the wind direction, since modern designs wind generators independently turn in the other direction.

For most areas of the Russian Federation, the most the best option there will be a horizontal orientation of the axis of rotation, the surface of the blades is curved concave, which the air flow flows around at an acute angle. The amount of power taken from the wind is affected by the area of ​​the blade. For an ordinary house, an area of ​​\u200b\u200b1.25 m 2 is enough.

The speed of a wind turbine depends on the number of blades. Wind turbines with one blade rotate the fastest. In such designs, a counterweight is used for balancing. It should also be taken into account that at low wind speeds, below 3 m/s, wind turbines become unable to take energy. In order for the unit to perceive a weak wind, the area of ​​​​its blades must be increased to at least 2 m 2.

Calculation of a wind generator

Before choosing a wind generator, it is necessary to determine the wind speed and direction that are most characteristic at the place of intended installation. It should be remembered that the rotation of the blades starts at a minimum wind speed of 2 m/s. The maximum efficiency can be achieved when this indicator reaches a value from 9 to 12 m / s. That is, in order to provide electricity to a small country house, you will need a generator with a minimum power of 1 kW / h and wind at a speed of at least 8 m / s.

Wind speed and propeller diameter have a direct impact on the power generated by a wind turbine. It is possible to accurately calculate the performance characteristics of a particular model using the following formulas:

  1. Calculations in accordance with the area of ​​rotation are performed as follows: P = 0.6 x S x V 3, where S is the area perpendicular to the direction of the wind (m 2), V is the wind speed (m / s), P is the power of the generator set ( kW).
  2. To calculate the electrical installation by the diameter of the screw, the formula is used: P \u003d D 2 x V 3 / 7000, in which D is the screw diameter (m), V is the wind speed (m / s), P is the generator power (kW).
  3. With more complex calculations air flow density is taken into account. For these purposes, there is a formula: P \u003d ξ x π x R 2 x 0.5 x V 3 x ρ x η red x η gene, where ξ is the coefficient of wind energy use (a measureless value), π = 3.14, R - rotor radius (m), V - air flow velocity (m / s), ρ - air density (kg / m 3), η ed - reducer efficiency (%), η gene - generator efficiency (%).

Thus, the electricity produced by the wind generator increases quantitatively in a cubic ratio with the increasing speed of the wind flow. For example, with an increase in wind speed by 2 times, the production of kinetic energy by the rotor will increase by 8 times.

When choosing a place to install a wind turbine, it is necessary to give preference to areas without large buildings and tall trees that create a barrier to the wind. The minimum distance from residential buildings is from 25 to 30 meters, otherwise the noise during work will create inconvenience and discomfort. The wind turbine rotor must be located at a height exceeding the nearest buildings by at least 3-5 m.

If it is not planned to connect a country house to a common network, in this case, you can use the options of combined systems. The operation of the wind turbine will be much more efficient when used in conjunction with a diesel generator or a solar battery.

How to make a wind generator with your own hands

Regardless of the type and design of the wind turbine, each device is equipped with similar elements as a basis. All models are equipped with generators, blades of various materials, lifts to provide the desired level of installation, as well as additional batteries and an electronic control system. The most simple to manufacture are rotary-type units or axial structures using magnets.

Option 1. Rotary design of the wind generator.

The design of a rotary wind generator uses two, four or more blades. Such wind generators are not able to fully provide electricity to large country houses. They are mainly used as an auxiliary source of electricity.

Depending on the design power of the windmill, the necessary materials and components are selected:

  • 12 volt car alternator and car battery.
  • Voltage regulator that converts alternating current from 12 to 220 volts.
  • capacity with large sizes. An aluminum bucket or stainless steel pot works best.
  • As a charger, you can use the relay removed from the car.
  • You will need a 12 V switch, a charge lamp with a controller, bolts with nuts and washers, and metal clamps with rubberized gaskets.
  • A three-core cable with a minimum cross section of 2.5 mm 2 and a conventional voltmeter taken from any measuring device.

First of all, the rotor is prepared from an existing metal container - a pot or bucket. It is divided into four equal parts, holes are made at the ends of the lines to facilitate separation into component parts. Then the container is cut with scissors for metal or a grinder. Rotor blades are cut out of the resulting blanks. All measurements must be carefully checked for dimensional conformity, otherwise the design will not work properly.

Next, the side of rotation of the generator pulley is determined. As a rule, it rotates clockwise, but it is better to check this. After that, the rotor part is connected to the generator. To avoid imbalance in the movement of the rotor, the mounting holes in both designs must be symmetrical.

To increase the speed of rotation, the edges of the blades should be slightly bent. As the bending angle increases, the air flows will be more effectively perceived by the rotary unit. As blades, not only elements of a cut container are used, but also individual parts connected to a metal blank having the shape of a circle.

After attaching the container to the generator, the entire resulting structure must be fully installed on the mast using metal clamps. Then the wiring is mounted and assembled. Each pin must be connected to its own connector. After connection, the wiring is attached to the mast with wire.

At the end of the assembly, the inverter, battery and load are connected. The battery is connected with a cable with a cross section of 3 mm 2, for all other connections a cross section of 2 mm 2 is sufficient. After that, the wind generator can be operated.

Option 2. Axial construction of a wind generator using magnets.

Axial windmills for the home are a design, one of the main elements of which are neodymium magnets. In terms of their performance, they are significantly ahead of conventional rotary units.

The rotor is the main element of the entire design of the wind turbine. For its manufacture, the hub of an automobile wheel complete with brake discs is best suited. The part that was in operation should be prepared - cleaned of dirt and rust, lubricated bearings.

Next, you need to correctly distribute and fix the magnets. In total, you will need 20 pieces, 25 x 8 mm in size. The magnetic field in them is located along the length. Even magnets will be poles, they are located on the entire plane of the disk, alternating through one. Then the pros and cons are determined. One magnet alternately touches the other magnets on the disk. If they attract, then the pole is positive.

With an increased number of poles, it is necessary to observe certain rules. In single-phase generators, the number of poles is the same as the number of magnets. Three-phase generators have a 4/3 ratio between magnets and poles and a 2/3 ratio between poles and coils. The installation of magnets is carried out perpendicular to the circumference of the disc. A paper template is used to evenly distribute them. First, the magnets are fixed with strong glue, and then finally fixed with epoxy.

If we compare single-phase and three-phase generators, then the performance of the former will be somewhat worse compared to the latter. This is due to high amplitude fluctuations in the network due to unstable current output. Therefore, vibration occurs in single-phase devices. In three-phase designs, this disadvantage is compensated by current loads from one phase to another. As a result, a constant power value is always ensured in the network. Due to vibration, the service life of single-phase systems is significantly shorter than that of three-phase systems. In addition, three-phase models have no noise during operation.

The height of the mast is approximately 6-12 m. It is installed in the center of the formwork and poured with concrete. Then a finished structure is installed on the mast, on which the screw is attached. The mast itself is fastened with cables.

Wind turbine blades

The efficiency of wind power installations largely depends on the design of the blades. First of all, this is their number and size, as well as the material from which the blades for the wind turbine will be made.

Factors affecting blade design:

  • Even the weakest wind can set the long blades in motion. However, too much length can slow down the speed of the wind wheel.
  • Increasing the total number of blades makes the wind wheel more responsive. That is, the more blades, the better the rotation starts. However, the power and speed will decrease, making such a device unsuitable for power generation.
  • The diameter and speed of rotation of the wind wheel affects the noise level generated by the device.

The number of blades must be combined with the installation site of the entire structure. Under the most optimal conditions, properly selected blades can provide maximum output from the wind turbine.

First of all, you need to determine in advance the required power and functionality of the device. To properly manufacture a wind generator, you need to study possible designs, as well as climatic conditions in which it will be used.

In addition to the total power, it is recommended to determine the value of the output power, also known as peak load. It represents the total number of appliances and equipment that will be turned on simultaneously with the operation of the wind turbine. If you need to increase this figure, it is recommended to use several inverters at once.

DIY wind generator 24v - 2500 watts

The need to save Natural resources forces most states to look for alternative sources of electricity. One such source is wind energy, which can be used to produce electrical energy in volumes sufficient to meet the needs of both domestic consumers and industrial enterprises. The basis of the design for generating electricity from wind is a generator mounted on a mast.

Wind generator device

The design of the wind farm includes the following elements:

  • Generator;
  • Mast;
  • Blades;
  • Anemometer;
  • Rechargeable batteries;
  • ATS device (automatic switching on of the reserve);
  • Transformer.

The principle of operation of a wind farm is based on the conversion of wind energy into rotational motion of the turbine. This happens with the help of blades (rotor). The wind follows the contour of the blades, causing them to rotate.

Modern wind farms have three blades. Their length can reach 56 meters. Rotation speed within 12-24 rpm. Reducers are used to increase the speed of rotation. The power of modern wind turbines can reach 750 kW.

The anemometer is designed to measure wind speed. It is mounted on the back side of the turbine casing. The wind speed information is analyzed by the built-in computer to generate the greatest amount of electricity.

The design of the wind farm can operate at a wind speed of 4 meters per second. When the wind speed reaches 25 meters per second, wind power plants, the principle of operation, which is based on the use of wind energy, automatically turn off. Uncontrolled rotation of the blades strong wind is one of the causes of accidents and destruction of the windmill.

The transformer converts the voltage to the values ​​necessary to transport electricity to the consumer through the wires of the power line. Typically, transformers are installed at the base of the mast.

The mast is an important structural element of a wind farm. The generation of the generator depends on its height. The height of the mast of modern windmills ranges from 70-120 meters. Some designs provide for the presence of helipads.

Installation of wind turbines

One of the necessary conditions for the full operation of the device is the choice of a suitable place for its placement. Ideally, this should be a hill with high speed winds at low turbulence.


If there is a forest nearby, then this will reduce the efficiency of the wind turbine. The absence of a high-voltage transmission line nearby will not make it possible to redirect the generated electricity to consumers.

Problems caused by the operation of wind farms

Despite the fact that wind turbines are a promising way to generate electricity, there are many problems associated with their operation. In particular, in European countries where wind energy is being actively introduced, many people complain about the discomfort caused by the close proximity to wind turbines.

In most countries, there are no laws that would clearly define how far from residential buildings they can be placed. Sometimes a wind generator can be seen already at a distance of 200-250 meters from the house. People complain about the loud noise that is carried hundreds of meters around. The shadow from the rotating blades of a windmill can be cast for several kilometers. This causes severe psychological discomfort.

The problems are caused by the fact that the full-scale use of wind energy began relatively recently. Powerful wind turbines have not been used before. Therefore, their impact on humans has not been fully studied. Laws are currently being developed to minimize the discomfort of operating these mechanisms.